In most urban environments, there is a decreasing quality of air available in the general atmosphere. This reduction in air quality is repeated within buildings and, in some instances, can even be worse. Smoking within an enclosed building is harmful not only in respect of passive smoking but also due to the reduction in oxygen content and general impurities provided into the air aside from nicotine or tar.
The decrease in air quality is not only due to a decrease in oxygen content but also a corresponding increase in a number of potentially harmful constituents or pollutants. These include an increase in suspended particles, carbon dioxide, carbon monoxide, nitrogen dioxide, bacteria, formaldehyde, total volatile organic compounds (TVOCs), ozone, radon, toxic moulds, ammonia, sulphur dioxide and organic odour causing compounds.
Traditional forms of manipulating the atmosphere within a room utilize air conditioning for temperature control and, either integrally or separately, air filtration units that seek to remove larger particulate material. Although the air conditioning units may be provided with some filtration, these filters are generally an after-thought merely to preclude coarse particles from going through the air conditioning system. Regardless, these filters are generally static filters in each of the air inlets or outlets throughout the building and quickly become clogged with particulate matter. This requires regular maintenance to clean and replace the filters. Failure to do so can quickly turn the filters into a breeding ground for harmful organisms rather than any attempt to improve air quality.
For domestic appliances, separate air filtration units utilizing HEPA filters are also known. However, these merely seek to filter particulate materials and do not improve or alter the composition of the air passing through the filter.
Other apparatus seeks to improve air quality only in a controlled and highly localized environment through such apparatus as oxygen ventilators. Such ventilators are provided with face masks or similar to improve the air quality to a single user. However, such ventilators are not generally suitable or adapted for use in a larger environment such as an apartment or similar.
One solution towards the improvement of indoor air quality has been already been described in International Publication No. WO 02/12796. This apparatus is generally directed to the treatment of air within an entire building although does apply in principle to single room environments also. However, in the case of domestic appliances in particular, matters of cost are of paramount importance perhaps requiring some simplification of the apparatus. Furthermore, it is important to reduce the maintenance and service requirements of the apparatus as much as possible to bring these within the scope and capabilities of a typical home user rather than an experienced service technician.